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1.
The biology of small marsupials is poorly known because most species are nocturnal and arboreal. Using the spool-and-line device, we investigated the use of vertical space by male and female Marmosops incanus in the Serra dos Órgãos National Park. Diameter and slopes of supports also were compared. The species was sexually dimorphic in body size, males weighing on average 72.6 g and females 48.1 g, but males and females did not differ in the frequency of ground movements (GM) and understory movements (UM), or in diameter and slopes of supports used. Males and females also used the forest strata similarly, moving 67% on the ground and 33% in the understory. Both sexes used 0.9–1.7 cm support diameters, and support slopes near the horizontal (more than 50% of cases), but preferred to access a given height by moving on high slope supports (mostly near 90°). Sexual dimorphism in body size does not seem to constrain movements of M. incanus. 相似文献
2.
A population viability analysis (PVA) using the computer package VORTEX was conducted to assess the minimum viable population
(MVP) of the Atlantic Forest endemic marsupial Micoureus paraguayanus. The objectives were: to estimate demographic and genetic MVPs that could be used as quasi-extinction thresholds for future
modeling, to estimate the minimum area of suitable habitat (MASH), and to use these results to apply IUCN red list criteria
so as to suggest its proper status classification. The model predicted that populations of 100 and 2000 individuals were necessary
to achieve demographic and genetic stability, respectively, within a time frame of 100 years. The model was sensitive to changes
in inbreeding depression, mortality and reproduction. MASH estimated to contain genetically viable populations reached 1300 ha.
Fortunately, there still are quite a number of forest remnants equal to or larger than this. Isolation is suggested as the
principal threat facing M. paraguayanus. Therefore, promoting conditions for dispersal together with efforts dealing with translocation, should prove to be the most
appropriate management strategies for M. paraguayanus at this stage. A landscape pattern composed of large patches holding MVPs and sets of smaller patches harboring viable metapopulations
that maximize probability of dispersal can provide a viable scenario for the conservation of M. paraguayanus. 相似文献
3.
Claire Pauline Rpke Ferrando Jenifer Martins Lamberto Natlia Oliveira Leiner 《Ethology : formerly Zeitschrift fur Tierpsychologie》2019,125(3):133-141
Space use patterns of a population are a result of the set of movements of its individuals, which are directly influenced by their attributes and environmental conditions. Understanding space use patterns and its determinants may give us insights about a species’ ecology, social and mating systems. Although echimyid rodents display a variety of mating and social systems, movements of burrowing species are poorly studied due to their cryptic habits. Hence, in this study, we evaluated the effects of body mass, sex, and palm fruit availability on space use patterns of the burrowing echimyid Clyomys laticeps, by measuring their daily home range (DHR) and intensity of habitat use. In 9 months of study in a “cerrado campo sujo” site, we tracked 14 adults with the spool‐and‐line in a backpack method. Adult males had larger DHR size than females, probably as a response to greater body mass and reproductive behavior. Furthermore, adult females had greater intensity of habitat use, presenting site fidelity, which can be due to offspring care as a response to non‐seasonal reproduction observed in our study and/or due to nest site defense strategy to avoid energetic costs associated with burrow construction. Differently from expected, food availability (i.e., Allagoptera campestris palm fruits) had no influence on the space use patterns of C. laticeps. As in other herbivorous rodents, shifts in proportion of consumed food items according to their availability may explain the lack of this influence in our study. Our findings suggest that space use patterns of C. laticeps are mainly explained by behavioral and physiological differences between sexes, including body mass and reproductive strategies. Additionally, larger male movements and female site fidelity suggest a solitary behavior and a polygynous mating system, although further studies regarding spatial organization and genetic structure are necessary to support these suggestions. 相似文献
4.
Jayme Augusto Prevedello Renato Garcia Rodrigues Emygdio Leite de Araujo Monteiro-Filho 《Mammalian Biology》2010,75(2):106-114
Habitat selection by small mammals is usually evaluated using data from live trapping, which provides little information about the movements of individuals. Few studies used movement data or compared the results of different sampling methods to study habitat selection by these animals. We evaluated habitat selection by the rodent Nectomys squamipes and the marsupial Micoureus paraguayanus in the Atlantic Forest of Brazil using the spool-and-line technique. We also determined if percentage of captures reflected the amount of movements in each habitat. Habitat selection was determined comparing use and availability of five habitat types at two spatial scales (movement paths and movement areas) using compositional analysis, which allowed ranking of habitats according to their relative use by animals. The use of available habitat types was non-random for both species at both spatial scales. The two species had contrasting habitat affinities directly related to their particular habits, with N. squamipes using predominantly the stream habitat, and M. paraguayanus using mainly the restinga forest habitat. Patterns of habitat selection were similar at both spatial scales probably due to the small size of movement areas, which may not represent habitat use at a broader scale. For both species, live trapping and movement data provided the same ranking in habitat use, demonstrating that simple capture indices may be used to study habitat selection by these species across different habitat types. 相似文献
5.
Nathan Charles Bass Joanna Day Tristan L. Guttridge Johann Mourier Nathan A. Knott Catarina Vila Pouca Culum Brown 《Journal of fish biology》2021,99(4):1455-1466
Examining the movement ecology of mesopredators is fundamental to developing an understanding of their biology, ecology and behaviour, as well as the communities and ecosystems they influence. The limited research on the residency and movements of benthic marine mesopredators has primarily used visual tags, which do not allow for the efficient and accurate monitoring of individual space use. In this study, the authors investigated the residency and movement patterns of Port Jackson sharks Heterodontus portusjacksoni (Meyer 1793) at a breeding aggregation site in Jervis Bay, south-eastern Australia, using passive acoustic telemetry to further our understanding of the movement ecology of these important mesopredators. Between 2012 and 2014, individuals were tagged with acoustic transmitters, and their residency and movements within the bay were monitored for up to 4 years. H. portusjacksoni showed strong preferences for particular reefs within and between breeding seasons. Males had significantly higher residency indices at their favoured sites relative to females, suggesting that males may be engaging in territorial behaviour. Conversely, female H. portusjacksoni exhibited higher roaming indices relative to males indicating that females may move between sites to assess males. Finally, H. portusjacksoni showed temporal variation in movements between reefs with individuals typically visiting more reefs at night relative to the day, dusk and dawn corresponding with their nocturnal habits. 相似文献
6.
Abstract: Despite outnumbering their temperate counterparts, tropical snake species have been poorly studied. Yet, the few tropical species that have been studied show a variety of behavioural traits beyond those described in temperate species. Here we reveal both age and sexual differences in the movements of tropical green pythons (Morelia viridis: Pythonidae). We radio‐tracked 27 individuals (17 females and 10 males) for up to 18 months, locating individuals during both the day and night. The home range size for adult females (mean ± SE of 6.21 ± 1.85 ha) was correlated with snout–vent length. Neither adult males nor juveniles had a stable home range. Adult females had stable home ranges that overlapped considerably with those of other females and yellow individuals. Multiple radio‐tracked adult males passed through the territory of radio‐tracked adult females during the study. Females of all sizes were more likely to change position each day than males. There were no differences between the sexes or size categories in the distances moved in most months, although the variation in movement distances was higher in the dry season than during the wet season. In the wet season (January–March) movement distances increased and these were size‐ and sex‐related. This increased activity may be associated with mate searching. Males of M. viridis may maximize their rate of encountering mature females by roaming rather than maintaining a home range. Juvenile green pythons moved distances equal to adult snakes in most months despite their comparatively small size. 相似文献
7.
We examined the diurnal refuges occupied by the nocturnal squirrelfish, Holocentrus rufus, to describe refuges and the behavior associated with their use and to determine which, if any, refuge characteristics were
selected. We tagged 21 H. rufus on two sites on a fringing reef in Barbados, West Indies, identified the refuges they used (n = 57), measured ten characteristics of each refuge and the surrounding microhabitat, and monitored their refuge use for 4 weeks.
To evaluate refuge selection, we measured the same characteristics on a comparable number of unused potential refuges (n = 67) on the same reefs and used classification tree models to determine which characteristics separated used from unused
refuges. Each fish used 1–9 refuges, which did not overlap among individuals and were defended against intrusion by conspecifics
and some heterospecifics. Fish with more than one refuge frequently moved among them. There was strong site fidelity with
no immigration of untagged fish or emigration of tagged fish on either reef during the study period and no additional refuges
being occupied over the 4-week period. Refuges were primarily holes, open at one or two ends, which varied in size, distance
from the reef edge, entrance orientation, and vertical relief at the entrance. Holes used as refuges differed significantly
from unused holes mainly in characteristics related to the vertical position of their entrance, but the classification tree
models differed for the two sites. This study provides the first detailed information on characteristics of daytime refuges
used by a nocturnally active reef fish and the first evidence of selectivity of refuges. It suggests that the abundance and
characteristics of holes on reefs could influence the density of H. rufus on natural reefs. 相似文献
8.
Wolfgang P. J. Dittus Shyamala M. Ratnayeke 《International journal of primatology》1989,10(3):215-234
Toque macaques (Macaca sinica),inhabiting natural forest at Polonnaruwa, Sri Lanka, are frequently injured in fights with conspecifics. The behavior of known
individuals when they were injured was compared to that after they had recovered their health. Thus, injured animals rested
and alloand autogroomed more, but they foraged less and initiated fewer aggressive episodes. They spent most time being sedentary
in the safety of arboreal refuges and reduced acrobatic movements by locomoting more often terrestrially. Other group members
showed no special tolerance (or altruism) toward injury victims during the costly and highly competitive activity of foraging
for food. In fact, some injured animals received more aggression, or lost dominance rank, and thereby had their competitive
abilities further impaired. Care for the injured was manifest mostly by grooming and wound cleaning. All hair in the area
surrounding a wound, as well as dirt, scabs, and fly larvae, were removed, and saliva was applied by licking the wound (wounds
so treated healed with no obvious signs of infection). (1) Injured macaques sought and received significantly more grooming
(owing to wound care); (2) the amount so received increased with the severity of the injury; and (3) the initiative of other
group members often compensated for a victim’s inability to solicit care. Juvenile males were especially attentive to injured
adult males, suggesting that they were investing in a social bond with these adults, which might reciprocate altruism toward
their juvenile caregivers in the future. Injured juvenile females received most care from their mothers. 相似文献
9.
The red panda Ailurus fulgens Cuvier, 1825 is endemic to the Himalayan-Hengduan Mountains. Many of its ecological traits are still poorly understood although
important from a scientific standpoint as a highly specialized bamboo feeder. To understand its food habits and space-use,
we carried out a field study from April 2002 to May 2003 in Fengtongzhai Nature Reserve, China. The results showed that red
pandas almost exclusively fed on Bashania faberi, but not on Yushania brevipaniculata in the study area. Besides differences in nutritional quality, accessibility to food items is perhaps another factor affecting
their utilization of bamboo species. B. faberi leaves are the highest in crude protein, being the primary year-round food source; new shoots and fruits of Sorbus, and Rubus are nutritious and digestible, seasonally occurred in their diet. Red pandas seemed to select most nutritious food items
to feed on. The home range of red pandas averaged 2.2 km2 across individuals (2.6 km2 for the males and 1.7 km2 for the females), and overlapped extensively (ranging 18.9–78.1%). No significant difference was found in monthly percentage
of total home range used among seasons and sexes. The daily movement distance was 455 m (447 m for the females and 463 m for
the males), significantly affected by sexes and months. Our findings indicated that food resource significantly influenced
behaviour of red pandas in foraging and space use, and their behavioural responses are adaptive being helpful to energy intake
and maintenance. 相似文献
10.
We studied ranging patterns of syntopic folivorous and granivorous gerbils (Meriones tamariscinus Pallas, 1773 andMeriones meridianus Pallas, 1773, respectively) by means of radiotracking and live-trapping in Kalmykia, southern Russia. We hypothesized that
ranging patterns exhibited by these rodents would differ in accordance with differences in their preferred diets. Trapping
and radiotracking were performed from 23 May to 20 June 2000 on a 12 ha grid divided into 20 × 20 m squares. To assess ranging
patterns we estimated the number of grid squares visited by an individual, 100% minimum convex polygon, mean squared distance
from the center, maximal distance between individual locations, linearity index, and distance measures at various temporal
scales. In accord with expectations, females of folivorousM. tamariscinus exhibited smaller ranges than females of granivorousM. meridianus. Contrary to our expectations both trapping and radiotracking data revealed similar “granivorous” ranging patterns in males
of both species of gerbils. MaleM. meridianus andM. tamariscinus were similar in number of burrows used, home range size, and distances traversed. No temporal dependence of distance measures
was revealed in either species; males of both species traversed similar distances regardless of time interval for distance
measures so that single-night movements and multiday movements did not differ in either species. High food selectivity in
maleM. tamariscinus is considered to be responsible for the “granivorous” pattern of space use in this folivorous species. 相似文献
11.
As the only obligatorily predatory primates, tarsiers are notoriously difficult to keep successfully in captivity. Here we report empirical and experimental results from a 5-year study of behavior and life history in captive Tarsius bancanus. Four reproducing adult tarsiers used space nonrandomly, preferring small-diameter vertical or near-vertical locomotor substrates at midlevel enclosure heights (1.2–2.1 m) for sleeping, scanning, and prey capture. The tarsiers were completely nocturnal, and spent 78% of the scotophase scanning, 13% sleeping, and 9% in prey capture and other activities. Only live crickets were eaten; prey capture rates were highest in the first hour after waking, but overall activity rates were highest later in the scotophase. Adult males and nonpregnant or lactating females ingested approximately 44.7–49.7 kJ/day. Growing and lactating individuals ingested approximately 84.4–94.1 KJ/day. An energetically conservative, sit-and-wait predatory strategy was employed, in which 88% of capture attempts were successful. Most successful prey captures involved reaching for, or leaping from, 90° or 60° supports in a horizontal or downward direction onto prey less than 0.6 m away. Virtually all prey captures were in arboreal locations, despite much higher densities of crickets on enclosure floors. Prey capture rates during the first hour of the nocturnal activity period were positively correlated with arboreal cricket densities. At constant arboreal cricket densities, capture rates were negatively correlated with ambient light intensity, with optimum levels for prey capture ranging from 0.1 to 2.0 Lux. In terms of social behavior, these T. bancanus were nongregarious. Females enforced interindividual spacing by chasing and displacing males. Chase/displacement rates increased significantly during late pregnancy and lactation, apparently in an attempt to keep males from harassing infants. There was no direct male parental care. Infants were precocial at birth, and grew at a rate of 0.35–0.5 g/day, until nutritional weaning at approximately 60 days of age. The implications of specialized predatory morphology and behavior for management are discussed. © 1993 Wiley-Liss, Inc. 相似文献
12.
Intraspecific microhabitat segregation is expected to arise when there are age- or sex-specific differences in predation risk.
The degree to which conspecific predation (cannibalism) can generate this risk, however, is poorly understood. In this paper,
we examine microhabitat use, cannibalism, and individual responses to the presence of conspecifics in Thermosphaeroma thermophilum, an endangered isopod crustacean species that is endemic to a single, thermal spring in Socorro, N.M. USA. In samples from
the natural habitat, juveniles (mancas) were found mainly on vegetation, whereas adults were found predominantly on bottom
sediments. Females were found on vegetation more often than males. In laboratory containers without refuges, males cannibalized
females, males and females cannibalized mancas, and mancas cannibalized each other, even in the presence of alternative food.
When placed in containers provided with refuges, mancas actively avoided adults. We suggest, therefore, that cannibalism in
T. thermophilum generates age-, size-, and sex-specific predation risks which are responsible for microhabitat segregation between mancas
and adults, and between males and females. Since interspecific predation in the spring is negligible, cannibalism appears
to play a significant role in population regulation and behavioral evolution in this species. We recommend, given the current
“endangered” status of this species, that microhabitat heterogeneity be maintained in its native spring because it provides
refuges from cannibalism and may support a larger and more viable natural population.
Received: 28 June 1996 / Accepted: 24 February 1997 相似文献
13.
The crab spider Misumenoides formosipes is an ambush predator whose males search for relatively sedentary females within a heterogeneous habitat. Females are receptive
to mating immediately after their adult molt and a male biased adult sex ratio together with precopulatory guarding places
a premium on male ability to locate females quickly. It is unknown what cues males use to find females; we report here on
male movements in association with floral cues. Males in field trials moved towards inflorescences more frequently when both
visual and chemical cues were available, than when chemical cues were eliminated. Males in lab trials chose an inflorescence
over leaf substrates even in the absence of visual cues. These findings support the hypothesis that M. formosipes males could utilize floral chemistry as a navigational cue in mate searches. 相似文献
14.
15.
Nishie H 《Primates; journal of primatology》2011,52(4):329-342
The aim of this study was to provide basic data on ant-fishing behavior among the M group chimpanzees at the Mahale Mountains
National Park, Tanzania. Ant-fishing is a type of tool-using behavior that has been exhibited by Mahale chimpanzees when feeding
upon arboreal carpenter ants (Camponotus spp.) since the 1970s, and is now regarded as a candidate of wild chimpanzee culture. Herein, I describe in detail the features
of ant-fishing shown by the Mahale M group chimpanzees: (1) 2 species of Camponotus ants (Camponotus sp. (chrysurus-complex) [C. sp.1] and C. brutus) were identified as the target species of ant-fishing, and C. sp.1 was selected intensively as the main target; (2) 24 species (92 individuals) of trees were identified as ant-fishing
sites–these were widely distributed throughout the western/lowland region of the M group’s home range, and the top 5 species
were used more frequently; (3) the efficiency of ant-fishing was influenced not only by the site choice or the skillfulness
of the chimpanzees, but inevitably by the condition of the ants; (4) the estimated nutritional intake from ant-fishing was
apparently negligible; (5) most of the M group members (50/60 individuals) older than 3 years of age successfully used tools
to fish for ants; and (6) female chimpanzees engaged in ant-fishing more frequently and for longer periods than males did.
Further, I compared the features of ant-fishing exhibited by the Mahale M group chimpanzees with those exhibited by the former
K group at Mahale and by other populations of wild chimpanzees. 相似文献
16.
The study of the locomotion and postures of arboreal squirrels may provide important contextual information on the evolution
of the morphology and ecology of sciurids. In this context, we studied the positional behaviour and habitat use of four adult
European red squirrels (Sciurus vulgaris L.) in a mixed coniferous forest in northern Greece. Our results show that, during the study period, S. vulgaris extensively used the forest canopy and the terminal branch zone. The use of small and medium supports of all orientations
was also particularly frequent. The positional profile of the species was characterized by the dominance of quadrupedal, clawed
and airborne locomotion along with seated and standing postures. Quadrupedalism and sitting appeared to promote terminal branch
use for food access and manipulation, while claw climbing favored vertical ranging and retreat to trees after terrestrial
foraging. Finally, leaping reduced energetic costs during travelling between food sites within the relatively dispersed forest.
These results and those of previous research on the positional behaviour of other squirrels reveal several trends related
to body size, arboreal or gliding habits and tropical or temperate forest distribution and contribute to the understanding
of evolutionary novelty in multiple levels within the sciurid radiation. 相似文献
17.
Males,but not females,perform strategic mate searching movements between host plants in a leaf beetle with scramble competition polygyny 下载免费PDF全文
Danilo G. Muniz Martha L. Baena Rogelio Macías‐Ordóñez Glauco Machado 《Ecology and evolution》2018,8(11):5828-5836
Mate searching is assumed to be performed mostly by males, but when females benefit from multiple mating or are under risk of failing to mate, they may also perform mate searching. This is especially important in scramble competition polygynies, in which mate searching is the main mechanism of mate competition. Typically, more mobile individuals are expected to achieve higher mating success because mobility increases their probability of finding mates. If we assume individual movements are mainly explained by mate searching in scramble competition polygynies, we can investigate searching strategies by asking when individuals should leave their location and where they should go. We hypothesize that individuals will leave their locations when mating opportunities are scarce and will seek spatially close sites with better mating opportunities. We tested these hypotheses for males and females of Leptinotarsa undecimlineata, a leaf beetle with scramble competition polygyny in which both sexes are promiscuous. Individuals mate and feed exclusively on Solanum plants, and thus, individual movements can be described as switches between plants. Females were less likely than males to leave isolated plants, and both males and females moved preferentially to neighboring plants. Males were more likely to leave when the local number of females was low, and the number of males was high. They moved to plants with more females, a behavior consistent with a mate searching strategy. Females were more likely to move to plants with fewer males and many females, a behavior consistent with male harassment avoidance. Strategic movement is widely considered in foraging context, but seldom in a mate searching context. Considering that selection to minimize searching costs, maximize mating success, and minimize harassment may be ubiquitous in nature, we argue that strategic movements by mate searching individuals are likely to occur in many species. 相似文献
18.
Haruki Ochi 《Ichthyological Research》1996,43(3):239-246
The breeding habits of 2 maternal mouthbrooding cichlids,Cyprichromis microlepidotus andParacyprichromis brieni, were investigated in Lake Tanganyika. Although spawning on the substrate in the male's mating territory is prevalent in
maternal mouthbrooders, bothC. microlepidotus andP. brieni spawned in the water column. MaleC. microlepidotus established their mating territories in the open water column, while maleP. brieni did so around fixed spawning sites near a vertical rock surface. In both species, females visited male mating territories,
departing soon after spawning and collecting the eggs. Sneaking, which was observed only inP. brieni, may be attributed to the presence of refuges for sneakers in this species. FemaleC. microlepidotus deposited their entire clutch of about 9 eggs in one male territory. In contrast, femaleP. brieni divided their clutch of about 11 eggs among several males. After the final egg-release, femaleC. microlepidotus repeatedly approached their mate, with the mouth near the abdomen of the latter (nuzzling), but femaleP. brieni often departed without nuzzling. Males may eject sperm during nuzzling to fertilize eggs inside the female's mouth. However,
maleP. brieni is also known to eject sperm near spawning females when the females are not nuzzling. Such behavior seems to be a male countermeasure
against female mate infidelity, because males could not ensure paternity of eggs by ejecting sperm only during female nuzzling. 相似文献
19.
Sharon Gursky 《International journal of primatology》2010,31(1):117-131
One of the most widely accepted explanations for the difference in the sex bias between mammals and birds is that male-biased
dispersal in mammals is due to the preponderance of polygynous mating systems exhibited by this class, whereas birds are predominantly
monogamous. Spectral tarsiers (Tarsius spectrum) are unusual in that they exhibit variation in its mating system. Although the majority of spectral tarsier groups are monogamous,
ca. 15% are polygynous. If mating system influences dispersal, then I predicted that the polygynous groups would exhibit male
biased dispersal whereas I predicted that the dispersal patterns of the monogamous groups would be analogous to that exhibited
by birds, specifically female biased. Alternatively, I hypothesized that ecological variation may influence dispersal habits
in this species. Specifically, I predicted that polygynous groups would exhibit greater habitat quality than monogamous groups.
The 2 hypotheses are not mutually exclusive. On the basis of 14 individuals birdbanded between 1994 and 1999, I determined
that individuals of both sexes were equally likely to disperse (males, n = 5; females, n = 9). Males dispersed twice as far as females did. The mean dispersal distance for males was 660 m, and for females it was
266 m. Females (77%) were more likely to form a territory adjacent to the parental territory than were males (20%). Individuals
exhibited relatively high amounts of site fidelity (86%) that were related to physical characteristics of the sleeping site.
Adults that dispersed a second time (n = 4) initially resided in trees that were shorter and had a smaller diameter-at-breast height than the trees of individuals
that exhibited site fidelity. The results of my study partly support the parental mating system hypothesis and also support
the habitat quality hypothesis. 相似文献
20.
Extreme sexual dimorphism suggests that the South American electric fish, Brachyhypopomus pinnicaudatus Hopkins (Copeia 1991:151–161, 1991) is polygynous. No field studies have been conducted on the social behavior of this common
gymnotiform species, in part because their nocturnal habits and densely vegetated habitat precludes direct observation in
the field. We conducted mark–recapture studies on B. pinnicaudatus in Uruguay to gather indirect evidence of their breeding system. Sex ratios of adults were highly skewed toward females 2–3 weeks
into the breeding season. Females moved twice as far as males on average (p = 0.016) and movement tracks of individual females overlapped one another but those of males did not. These data support
the hypothesis that B. pinnicaudatus is polygynous or polygynandrous, and suggest that they use space in a manner consistent with exploded lek polygyny or iteroparous
nest site polygynandry models. Fish detected within 2 m of each other were more aggregated than chance, both day and night,
suggesting they maintain social groupings or alerting networks. 相似文献